About 30 aftershocks were felt in the northern Mexican state of Baja California after Sunday's 7.2-magnitude quake.
The authorities said Monday that the quake left two dead and around 100 injured in a border area between Mexico and the United States, dpa reported.
Many opted to sleep outdoors to avoid danger from aftershocks measuring 3.5-4.9 on the Richter scale, according to Mexico's seismological service.
Sunday's quake was felt on both sides of the border, particularly in the cities of Mexicali, Tijuana, Calexico, San Diego and Los Angeles. It was stronger than the one which killed an estimated 220,000 people in Haiti in January.
Buildings, roads and bridges, including the pedestrian border bridge linking Mexicali and Calexi, suffered damage or collapsed. The quake and its aftershocks triggered some hysteria in the population.
The epicentre was 26 kilometres south-south-west of Guadalupe Victoria in Baja California, at a depth of 32 kilometres, the US Geological Survey said.
Baja California Governor Jose Guadalupe Osuna declared a state of emergency in the state capital Mexicali, a city of about 1 million people.
"The most important thing is to safeguard the physical integrity of Baja Californians," he said.
A 94-year-old man was killed when he was crushed by a collapsing wall. Another person was fatally run over by a car when he ran out in panic.
The quake caused outages in electricity, telephone and water supply. It also caused isolated fires.
This was the largest-magnitude quake in Baja California since 1940, when a tremblor measured 7.1.
The Federal Electricity Commission said in a statement that the power line to Mexicali from Tijuana suffered damage, which affected at least two power plants. The statement said work was ongoing in the hope of "fully restoring supply within a few hours."
The authorities suspended school at all levels in Mexicali.